Chevrolet Beretta Back Up Light Bulb Size

The Chevrolet Beretta back up light utilizes bulb size P21W and bulb size 1156 for various applications. Available data for the specified components covers the range from 1987 through 1994.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1987-1994	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156

Other Locations

Additional Notes

The Chevrolet Beretta uses the 1156 bulb for its back up light across all listed model years, spanning 1987-1994.
The 1156 is a single-filament bulb, meaning it serves one lighting function only, which is consistent with its role as a dedicated back up light.
It operates at 12 volts and 21 watts, placing it in the standard range for incandescent automotive reverse lighting.
The 1156 uses a BA15s bayonet base, a single-contact mount where the "s" denotes a single pin, distinguishing it from the dual-contact BA15d base found on other bulb types.
The 1156 is an ANSI-standardized bulb recognized in both the United States and Canada, meaning it conforms to a defined set of electrical and physical specifications across manufacturers.
Because the BA15s base is single-contact, it is not interchangeable with visually similar bulbs that use a BA15d base, such as the 1157, despite sharing the same base collar size.